Physiology Review Part 2

All of the following are functions controlled by the skeletal muscle EXCEPT?

• Movement of the whole body or part of the body

• maintain blood pressure and flow

• Emptying contents of certain organs to the external environment

• Manipulation of external objects

Which is true concerning the structure of skeletal muscle

• Have contractile apparatus

• Have Muscle fibers

• Contain thin and thick filaments

• Two of these

• None of these

During contractions of the sarcomere what band/zone shortens horizontally?

• L- Band

• I- Band

• H Zone

• two of these

The thick filament contains _____ but NOT _____

• Sarcomere, Sarcoplasmic Reticulum

• Myosin, Actin

• Actin, Myosin

• Tail, Head

The thin filament contains ____ but NOT_____

• Actin, Myosin

• Actin, Tropomyosoin

• Troponin, Tropmyosin

• Myosin, Actin

During Calcium Release, this travels down the T-tubule, and open VG DHP receptors

• ACh

  (Acetylcholine)

• Action potential

• Action Nuerons

• Calcium

During Calcium Release:

After the AP travels down the T-tubule, triggering the opening of VG DHP receptors what happens?

• Ca++ enters the cell through VG Ca++ channels

• SR opens, Ca++ enters the cytoplasm

• Contraction(Excitation contration coupling)

• RR opens, and allows Ca++ to enter the cytoplasm

What is the role of Ca++

• create a contraction

• Combine with troponin

• Move myosin out of the way

• None of these

Power Stroke:

1. High energy state(Resting)

2.___________________

3. Phosphate falls off

4._______!!!

5. ___________

6. Cross bridge breaks

7. ________(hint: LE to HE)

• 2. Cross Bridge Formed

  4. Power Stroke

  5. ATP Binds to actin

  7. Myosin re-energized

• 2. Cross Bridge formed

  4. ATP Binds to myosin

  5. Power stroke

  7. Actin re-energized

• 2. Cross Bridge Formed

  4. Power Stroke

  5. ATP binds to myosin

  7. Myosin re-energized

• 2. Cross Bridge Formed

  4. ATP Binds to Myosin

  5. Myosin re-energized

  6. Power Stroke

During Relaxation what occurs?

• ACh is removed

• ACh-esterase removes ACh

• The muscle relaxes

• Troponin and tropomyosin can resume their blocking role

• All of these answers are correct